Knox Sexual Offences and Child Abuse Investigation Team detectives are appealing for witnesses following an alleged indecent act in Ferntree Gully this month, Victoria Police say.
Investigators have been told a 23-year-old woman and a 4-year-old child were in a reserve in Mossfield Avenue about 4.30pm on 16 November.
The woman saw a man walking around the reserve, he then allegedly stood behind her and the child with his genitals exposed and was making obscene gestures.
The man is described as being aged in his late 40s or early 50s and was wearing an orange t-shirt, blue track pants and white runners.
Investigators have released a facial composite of a man they believe may be able to assist with their enquiries.
Anyone with information should contact Crime Stoppers.
